Study Suggests Melting in Arctic Could Release Heat-trapping Gases
2020-07-27
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1A new study suggests that increased warming in Arctic areas could release huge amounts of carbon into the atmosphere.
2The study centered on the permafrost layer beneath Arctic soil.
3The researchers said melting of this layer could release billions of tons of carbon into the atmosphere, with big effects on worldwide temperatures.
4Permafrost is a layer of soil in the world's Arctic and Antarctic areas.
5It has, in some cases, remained frozen for many years.
6Permafrost is important to the world's climate because it is believed to store two times the amount of carbon as there is in the atmosphere.
7The study was published this month in the science journal Nature Geoscience.
8Researchers examined how the top layer of this frozen soil warms during the summer.
9That is when plants and microorganisms come to life.
10The microorganisms eat plant roots and "breathe" like all living organisms, releasing carbon dioxide which is considered a heat-trapping, greenhouse gas.
11Scientists call this process rhizosphere priming.
12The researchers say as more frozen soil warms up, more plant roots are becoming exposed to microorganisms.
13As a result more carbon dioxide is being released.
14The researchers estimated the process could add as much as 40 billion tons of carbon to the atmosphere by the year 2100.
15Until now, the United Nations Environment Programme had estimated that global emissions of carbon gases must fall by 7.6 percent every year for the next 10 years.
16That is what scientists say would be needed to prevent world temperatures from rising more than 1.5 degrees Celsius -the main temperature goal of the Paris Agreement.
17But the writers of the new study note that their estimates are currently "unaccounted for" in global emission predictions.
18"To keep warming below 1.5 or 2 °C," the authors wrote, emissions "may need to be even more constrained."
19Researchers suggest that warming in the Arctic is worse than in other places.
20Studies by the United States space agency and the U.S. National Oceanic and Atmospheric Administration suggest that the past 10 years have been the hottest on record.
21In the Arctic, air temperatures are rising two times as fast as the global average.
22I'm John Russell.
1A new study suggests that increased warming in Arctic areas could release huge amounts of carbon into the atmosphere. 2The study centered on the permafrost layer beneath Arctic soil. The researchers said melting of this layer could release billions of tons of carbon into the atmosphere, with big effects on worldwide temperatures. 3Permafrost is a layer of soil in the world's Arctic and Antarctic areas. It has, in some cases, remained frozen for many years. Permafrost is important to the world's climate because it is believed to store two times the amount of carbon as there is in the atmosphere. 4The study was published this month in the science journal Nature Geoscience. Researchers examined how the top layer of this frozen soil warms during the summer. That is when plants and microorganisms come to life. The microorganisms eat plant roots and "breathe" like all living organisms, releasing carbon dioxide which is considered a heat-trapping, greenhouse gas. Scientists call this process rhizosphere priming. 5The researchers say as more frozen soil warms up, more plant roots are becoming exposed to microorganisms. As a result more carbon dioxide is being released. The researchers estimated the process could add as much as 40 billion tons of carbon to the atmosphere by the year 2100. 6Until now, the United Nations Environment Programme had estimated that global emissions of carbon gases must fall by 7.6 percent every year for the next 10 years. That is what scientists say would be needed to prevent world temperatures from rising more than 1.5 degrees Celsius -the main temperature goal of the Paris Agreement. 7But the writers of the new study note that their estimates are currently "unaccounted for" in global emission predictions. "To keep warming below 1.5 or 2 °C," the authors wrote, emissions "may need to be even more constrained." 8Researchers suggest that warming in the Arctic is worse than in other places. Studies by the United States space agency and the U.S. National Oceanic and Atmospheric Administration suggest that the past 10 years have been the hottest on record. In the Arctic, air temperatures are rising two times as fast as the global average. 9I'm John Russell. 10John Russell adapted this story from a report by VOA. Mario Ritter Jr. was the editor. 11_______________________________________________________________ 12Words in This Story 13permafrost - n. technical : a layer of soil that is always frozen in very cold regions of the world 14emission -- n. something sent out or given off 15unaccounted - adj. unexplained, not included in; the act of producing or sending out something (such as energy or gas) from a source 16prediction - n. the action of saying something will happen; a forecast 17constrain - v. to limit or restrict the scope or activity of something